# Dual Chemical Looping/Catalytic Process for Alkylation of Benzene With Ethane and Propane Yielding Ethylbenzene and Cumene Over Copper‐Containing Mordenite

## TL;DR

A new chemical process uses copper-containing mordenite to efficiently convert alkanes into alkylated aromatics like ethylbenzene and cumene in a single step.

## Contribution

A dual chemical looping/catalytic process is introduced for direct alkylation of benzene using alkanes with high selectivity and efficiency.

## Key findings

- The process yields up to 25% alkylated aromatics with over 97% selectivity per cycle.
- A π-bound Cu(I)–olefin intermediate and Brønsted acid sites facilitate the alkylation reaction.
- A bifunctional pathway involving Cu(I) and acid sites has a much lower energy barrier than Cu(I)-only mechanisms.

## Abstract

Given the sustained demand for alkylated aromatics and the strained olefin market, there is an urgent need to develop efficient one‐step processes for the direct alkylation of aromatics using alkanes instead of olefins. Such technologies offer greater energy efficiency and sustainability by eliminating the need for separate, energy‐intensive alkane dehydrogenation steps. In this work, we report a dual chemical looping / catalytic process that couples alkane dehydrogenation with aromatic alkylation over a copper‐containing mordenite yielding up to 25% of alkylated aromatics with >97% selectivity per cycle. In situ MAS NMR and FTIR spectroscopies combined with DFT calculations showed that the alkylation of benzene with alkanes proceeds via a π‐bounded Cu(I)‐olefin intermediate, which subsequently interacts with benzene, catalyzed by Brønsted acid sites, leading to alkylated products that readily desorb from the active material into the gas phase. DFT calculations show that alkylation mediated solely by Cu(I) has prohibitively high barriers (>1.8 eV), whereas a bi‐functional pathway involving both Cu(I) and Brønsted acid sites can proceed with significantly lower barrier (0.8 eV) through a concerted C–C bond formation and proton transfer step.

We report a dual chemical looping/catalytic process coupling alkane dehydrogenation with aromatic alkylation over Cu‐mordenite, yielding up to 25% alkylated aromatics with >95% selectivity per cycle. In situ NMR, FTIR spectroscopy, and DFT show alkylation proceeds via a π‐bound Cu(I)–olefin intermediate and Brønsted acid sites. DFT reveals a low‐barrier bifunctional pathway versus prohibitively high barriers for direct Cu(I)‐mediated mechanism.